The ship that shot to fame as the setting for the legendary American TV series, in which lonely passengers found love, had been under police surveillance since it sailed into Greece.

Now Greek officials are saying the Love Boat with its 600 mostly American and British passengers will be barred from leaving the port of Piraeus until an investigation into the heroin find is completed.

The discovery of 25 kg of heroin on board the fabled vessel on Thursday means the luxury cruise ship may have to stay in Greece for days.

Major tool for smugglers

Appearing before a public prosecutor, two Filipino crew members said it was not the first time they had smuggled drugs on the famous boat.

Each crew member was ready to fall in love (again) each week

For years the ship, Pacific Princess, was used as the setting for the legendary Love Boat television series, which contributed to the rise of the luxury holiday cruise.

The drugs were discovered after the ship arrived at the port near Athens from Istanbul, Turkey, as part of a two-week cruise in the Mediterranean.

Now Greek police say there is mounting evidence the luxury liner has become a major tool for smugglers bent on trafficking drugs around the Mediterranean.

Gwyn Hughes, spokesman for the London-based P&O Cruises, which owns the Pacific Princess, said a few passengers had returned home on their own but most were "enjoying their stay in Athens".